[azurezyq]

"a thing with fixed cost", just imagine the billboard in downtown. The cost is finite. But you'll know that the price would be aligned with ups and downs of the demand. You may use auction model, or you can continuously tune the price. Actually they may converge similarly, to the principles of free market.

Same thing with real estates, or stocks.

However the iPhone example you mentioned follows a different scheme. iPhone is not something people competing for, as long as stock lasts.